1. Technical Field
The present invention relates generally to aircraft launchers, and more specifically, to unmanned air vehicle (UAV) launchers.
2. Related Art
Three major types of UAV launchers known in the art are mechanical spring launchers, pneumatic launchers, and hydro-pneumatic launchers. Typically, hydro-pneumatic launchers are the most powerful and compact of known UAV launchers, and as a result, hydro-pneumatic launchers account for the majority of launchers on the market today.
Most known UAV launchers use an inclined rail in conjunction with a system to accelerate the UAV up the rail for launch, such as a shuttle. In many cases, the length of the rail is too large to facilitate tactical transport and mobility of the launcher when in its operative state. Thus, most known UAV launchers are transported in a partially disassembled state, and assembled at the launch site. Accordingly, minimizing the time and complexity of the assembly and disassembly process is typically the subject of most UAV design efforts.
Known UAV launchers are typically large in size. The size of the launchers can create problems in military environments, such as, for example:
(1) When used in shipboard applications, the size of the UAV launcher may exceed the amount of deck space that is available.
(2) The large size of known launchers can make redirection of the launcher (e.g., in response to wind changes) difficult. Sometimes, disassembly and reassembly are required for direction changes, which can require more time and personnel than are available. Consequently, users sometimes launch the UAV in wind conditions that jeopardize the aircraft (e.g., a tail wind).
(3) Protecting a deployed UAV launcher from adverse environmental conditions can be impractical when the launcher is large. This means the launcher design may suffer reliability degradation during weather events such as snow and ice, or environmental issues such as dust and sand. As a result, crews sometimes need to do maintenance, such as removing ice from the rails before the launcher can be used.
UAV launchers using relatively short rails (in contrast to the large launchers discussed above) can have setbacks as well. UAV launchers with short rails typically impart large launching loads over the short span of the rails. As a result, the UAV may need to be reinforced to survive these loads, which can increase the weight of the UAV. The increased weight of the UAV may have undesirable effects on it, for example, it may reduce the endurance of the UAV.